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[1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.
The polar bear (Ursus maritimus) is a large bear native to the Arctic and nearby areas. It is closely related to the brown bear, and the two species can interbreed.The polar bear is the largest extant species of bear and land carnivore, with adult males weighing 300–800 kg (660–1,760 lb).
Gilbert N. Lewis introduced the concepts of both the electron pair and the covalent bond in a landmark paper he published in 1916. [1] [2] MO diagrams depicting covalent (left) and polar covalent (right) bonding in a diatomic molecule. In both cases a bond is created by the formation of an electron pair.
The skeletal formula of the antidepressant drug escitalopram, featuring skeletal representations of heteroatoms, a triple bond, phenyl groups and stereochemistry. The skeletal formula, line-angle formula, bond-line formula or shorthand formula of an organic compound is a type of molecular structural formula that serves as a shorthand representation of a molecule's bonding and some details of ...
Tetrahedral structure of water. The pairs often exhibit a negative polar character with their high charge density and are located closer to the atomic nucleus on average compared to the bonding pair of electrons. The presence of a lone pair decreases the bond angle between the bonding pair of electrons, due to their high electric charge, which ...
The term dipolar bond is used in organic chemistry for compounds such as amine oxides for which the electronic structure can be described in terms of the basic amine donating two electrons to an oxygen atom. R 3 N → O. The arrow → indicates that both electrons in the bond originate from the amine moiety. In a standard covalent bond each ...
The most common Lewis bases are anions. The strength of Lewis basicity correlates with the pK a of the parent acid: acids with high pK a 's give good Lewis bases. As usual, a weaker acid has a stronger conjugate base. Examples of Lewis bases based on the general definition of electron pair donor include: simple anions, such as H − and F −
BF 3 + BCl 3 → BF 2 Cl + BCl 2 F. Because of the facility of this exchange process, the mixed halides cannot be obtained in pure form. Boron trifluoride is a versatile Lewis acid that forms adducts with such Lewis bases as fluoride and ethers: CsF + BF 3 → Cs[BF 4] O(CH 2 CH 3) 2 + BF 3 → BF 3 ·O(CH 2 CH 3) 2